The island was discovered and named by the British explorer William Smith in 1819.[5] It is approximately 95 km (59 mi) long and 25 km (16 mi) wide with a land area of 1,150 square kilometres (444 sq mi). Over 90% of the island's surface is permanently glaciated.[5] In 1821, 11 men of the sealing vessel Lord Melville survived the winter on the island, the first men to do so in Antarctica[6]

Human habitation of King George Island is limited to research stations belonging to Argentina, Brazil, Chile, China, Ecuador, South Korea, Peru, Poland, Russia, Uruguay, and The United States. Most of these stations are permanently staffed, carrying out research into areas as diverse as biology, ecology, geology, and palaeontology. Teniente Marsh, the Chilean Station on the Fildes Peninsula, is operated as a permanent village with an airstrip (with large hanger and control tower along with other buildings), cafeterias for personnel of its several agencies there, a bank, a post office and comfortable ranch-style family homes with children. Chile (like Argentina and Great Britain) regards all of the Antarctic Peninsula and South Shetland Islands as part of that country's territory, however the terms of the Antarctic Treaty allow Chile to colonize the Fildes Peninsula without overtly pursuing its territorial claims.[7] The Chinese "Great Wall" base features an indoor multipurpose room which serves as a full-size basketball court.

In October 2013, American heavy metal band Metallica announced that it would perform a concert sponsored by The Coca Cola Company at Carlini Station heliport.[8]The concert took place on December 8, 2013.[9]